diff options
| author | Stephen Hemminger <shemminger@osdl.org> | 2006-02-06 15:42:45 -0800 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2006-02-09 23:20:15 -0800 |
| commit | a426fa9147f034d5355875ffcb91f0a61e5b393a (patch) | |
| tree | 9ae78d4cf9ae05fc71183e1b3a23244dc2cd3bc2 | |
| parent | ec81e3178071f3747bd1522c959972105584514b (diff) | |
[PATCH] bridge: fix RCU race on device removal
Patch to 2.6.15 stable kernel to fix race conditions on device
removal. These are reproducible by doing delif while packets are
in flight.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | net/bridge/br_if.c | 7 | ||||
| -rw-r--r-- | net/bridge/br_input.c | 10 | ||||
| -rw-r--r-- | net/bridge/br_stp_bpdu.c | 8 |
3 files changed, 16 insertions, 9 deletions
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c index 975abe254b7a..c085d7586e99 100644 --- a/net/bridge/br_if.c +++ b/net/bridge/br_if.c @@ -99,7 +99,6 @@ static void del_nbp(struct net_bridge_port *p) struct net_bridge *br = p->br; struct net_device *dev = p->dev; - dev->br_port = NULL; dev_set_promiscuity(dev, -1); spin_lock_bh(&br->lock); @@ -110,9 +109,7 @@ static void del_nbp(struct net_bridge_port *p) list_del_rcu(&p->list); - del_timer_sync(&p->message_age_timer); - del_timer_sync(&p->forward_delay_timer); - del_timer_sync(&p->hold_timer); + rcu_assign_pointer(dev->br_port, NULL); call_rcu(&p->rcu, destroy_nbp_rcu); } @@ -217,7 +214,6 @@ static struct net_bridge_port *new_nbp(struct net_bridge *br, p->dev = dev; p->path_cost = cost; p->priority = 0x8000 >> BR_PORT_BITS; - dev->br_port = p; p->port_no = index; br_init_port(p); p->state = BR_STATE_DISABLED; @@ -360,6 +356,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev) else if ((err = br_sysfs_addif(p))) del_nbp(p); else { + rcu_assign_pointer(dev->br_port, p); dev_set_promiscuity(dev, 1); list_add_rcu(&p->list, &br->port_list); diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index b88220a64cd8..c027ac3b9043 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -45,11 +45,17 @@ static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb) int br_handle_frame_finish(struct sk_buff *skb) { const unsigned char *dest = eth_hdr(skb)->h_dest; - struct net_bridge_port *p = skb->dev->br_port; - struct net_bridge *br = p->br; + struct net_bridge_port *p = rcu_dereference(skb->dev->br_port); + struct net_bridge *br; struct net_bridge_fdb_entry *dst; int passedup = 0; + if (unlikely(!p || p->state == BR_STATE_DISABLED)) { + kfree_skb(skb); + return 0; + } + + br = p->br; /* insert into forwarding database after filtering to avoid spoofing */ br_fdb_update(p->br, p, eth_hdr(skb)->h_source); diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c index d071f1c9ad0b..78b8f2806359 100644 --- a/net/bridge/br_stp_bpdu.c +++ b/net/bridge/br_stp_bpdu.c @@ -136,10 +136,13 @@ static const unsigned char header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00}; /* NO locks */ int br_stp_handle_bpdu(struct sk_buff *skb) { - struct net_bridge_port *p = skb->dev->br_port; - struct net_bridge *br = p->br; + struct net_bridge_port *p = rcu_dereference(skb->dev->br_port); + struct net_bridge *br; unsigned char *buf; + if (!p) + goto err; + /* insert into forwarding database after filtering to avoid spoofing */ br_fdb_update(p->br, p, eth_hdr(skb)->h_source); @@ -150,6 +153,7 @@ int br_stp_handle_bpdu(struct sk_buff *skb) buf = skb_pull(skb, sizeof(header)); + br = p->br; spin_lock_bh(&br->lock); if (p->state == BR_STATE_DISABLED || !(br->dev->flags & IFF_UP) |